Method for defrosting a gas cooling arrangement of a freezer

Abstract

The present invention relates to a defroster ( 5 - 10 ) for defrosting a gas cooling arrangement ( 4 ) of a freezer, comprising a sound generator ( 5 ) arranged to generate a sound pulse and to subject said gas cooling arrangement ( 4 ) to said sound pulse such that an amount of frost formed on said gas cooling arrangement ( 4 ) is reduced by removing frost formed on said gas cooling arrangement ( 4 ) by means of sound energy in said sound pulse. The present invention also relates to a freezer system comprising such a defroster ( 5 - 10 ) and a gas cooling arrangement ( 4 ). The present invention also relates to a method for defrosting a gas cooling arrangement ( 4 ) of a freezer. Figure elected for publication.

1 . A method for defrosting a gas cooling arrangement of a freezer, the gas cooling arrangement being adapted to cool a gaseous medium passing the gas cooling arrangement, the method comprising:
 generating a sound pulse; and   subjecting said gas cooling arrangement to said sound pulse such that an amount of frost formed on said gas cooling arrangement is reduced by removing frost formed on said gas cooling arrangement by means of sound energy in said sound pulse.   
     
     
         2 . The method as claimed in  claim 1 , wherein the sound pulse is generated with a frequency below 300 Hz, preferably between 10-250 Hz, more preferably between 150-250 Hz. 
     
     
         3 . The method as claimed in  claim 1 , wherein said sound pulse is generated with a duration between 0.1 and 15 seconds, preferably between 1 and 10 seconds, more preferably between 2 and 5 seconds. 
     
     
         4 . The method as claimed in  claim 1 , wherein said sound pulse is generated at predetermined time intervals. 
     
     
         5 . The method as claimed in  claim 1 , wherein said sound pulse is generated at time intervals based on current amount of frost on said gas cooling arrangement. 
     
     
         6 . The method as claimed in  claim 4 , wherein said time intervals are set to be at most ten times an hour. 
     
     
         7 . The method as claimed in  claim 1 , wherein said sound pulse is directed towards said gas cooling arrangement. 
     
     
         8 . The method as claimed in  claim 1 , wherein said sound pulse exhibits a sound pressure level (SPL) at said gas cooling arrangement of 100-160 dB SPL , preferably 120-150 dB SPL . 
     
     
         9 . A freezer system comprised in a housing, comprising:
 a gas cooling arrangement; and   a sound generator arranged to generate a sound pulse and to subject said gas cooling arrangement to said sound pulse such that an amount of frost formed on said gas cooling arrangement is reduced by removing frost formed on said gas cooling arrangement by means of sound energy in said sound pulse.   
     
     
         10 . The freezer system as claimed in  claim 9 , wherein the sound generator is arranged to generate sound with a frequency below 300 Hz, preferably between 10-250 Hz, more preferably between 150-250 Hz. 
     
     
         11 . The freezer system as claimed in  claim 9 , wherein a duration of said sound pulse is between 0.1 and 15 seconds, preferably between 1 and 10 seconds, more preferably between 2 and 5 seconds. 
     
     
         12 . The freezer system as claimed in  claim 9 , wherein said sound generator is arranged to generate sound pulses at predetermined time intervals. 
     
     
         13 . The freezer system as claimed in  claim 9 , wherein said sound generator is arranged to generate sound pulses at intervals based on current amount of frost on said gas cooling arrangement. 
     
     
         14 . The freezer system as claimed in  claim 9 , wherein said sound generator comprises a sound horn powered by compressed air. 
     
     
         15 . A defroster for defrosting a gas cooling arrangement of a freezer, comprising a sound generator arranged to generate a sound pulse and to subject said gas cooling arrangement to said sound pulse such that an amount of frost formed on said gas cooling arrangement is reduced by removing frost formed on said gas cooling arrangement by means of sound energy in said sound pulse. 
     
     
         16 . The method of  claim 5 , wherein the current amount of frost is such that:
 the gas cooling arrangement has declined below a desired level of effectiveness; or   the frost has reached a level that the frost is especially effectively affected by the sound pulse used.   
     
     
         17 . The method of  claim 5 , wherein the current amount of frost is determined by:
 analyzing an image of the gas cooling arrangement; and/or   measuring the differential pressure over the gas cooling arrangement.   
     
     
         18 . The defroster as claimed in  claim 15 , wherein said sound generator is arranged to generate sound pulses at predetermined time intervals. 
     
     
         19 . The defroster as claimed in  claim 18 , wherein said sound generator is arranged to generate sound pulses at time intervals based on current amount of frost on said gas cooling arrangement. 
     
     
         20 . The defroster of  claim 19 , wherein the current amount of frost is determined by:
 analyzing an image of the gas cooling arrangement; and/or   measuring the differential pressure on the gas cooling arrangement.